$\log\left(x-1\right)-log\left(1-y\right)=0$

$\int\frac{2}{5}\sec\left(3x-1\right)dx$

$2x\le4$

$\frac{d}{dx}\left(1-x\right)tanh^{-1}x$

$\lim_{x\to0}\left(\frac{2\left(e^x-1-x\right)}{1-cos\left(x\right)}\right)$

$3\cos\left(x\right)=3-3\sin\left(x\right)$

$30+5+8-3+1-4$